DC Electrical Problem

designbug · Posted: Mon Jul 27, 2009 10:58 am Post subject: DC Electrical Problem

Hi All,

This past Saturday I discovered that my pilot station electrical panel, GPS and VHF Radio stopped working. The engine starts fine, the AC power through the shore connection works and so does the anchor windlass. I checked all the fuses, which all seemed fine, and checked all the reset buttons on the panel itself. There is a reset switch near the battery selector switch which I have reset several times to no avail.

My wife, Laurie, said that she turned on our inverter (300 watt?) which was attached to the panel's 12 volt plug while we were connected to shore power to run the ipod - could this have caused some kind of short?

Any suggestions would be appreciated.

Thanks, Dick

Byrdman · Posted: Mon Jul 27, 2009 11:17 am Post subject:

Don't think the inverter and ipod is the issue.
How many batteries do you have on your boat?
Depending on how whoever wired in your batteries, some items may be wired to the crank battery...which seems to be fine....while others may get power from one, or more "house" batteries.

Byrdman

designbug · Posted: Mon Jul 27, 2009 11:48 am Post subject:

How many batteries do you have on your boat?
Depending on how whoever wired in your batteries, some items may be wired to the crank battery...which seems to be fine....while others may get power from one, or more "house" batteries.

Byrdman

Hi Byrdman,

I have two Group 24 batteries, which I believe is the standard CD25 setup. Using the battery selector switch either of the batteries can be used to start the engine and both appear to be working (I'll retest again this evening to be sure).

Thanks, Dick

Sea Wolf · Posted: Mon Jul 27, 2009 3:12 pm Post subject:

Dick-

What I'd do is get a voltmeter or continuity tester and start back as far as you can and trace the power's flow/continuity from the battery(s) forward through the fuses and switch panel to the dash, looking for the break in continuity or voltage loss in the circuit.

Joe. Teeth

designbug · Posted: Tue Jul 28, 2009 10:28 am Post subject:

I think I found the problem. I bypassed the main circuit breaker and dc power was restored. I will replace the main circuit breaker this weekend.

Thanks for everyone's advice, Dick

Byrdman · Posted: Tue Jul 28, 2009 10:36 am Post subject:

Cool.... but, now,.... what caused the main breaker to go bad? That is very, very rare.... I think..

Byrdman

designbug · Posted: Tue Jul 28, 2009 11:00 am Post subject:

Good question? In my research I noticed that Bill on Barnacle Bill and Pat on Daydream had similar problems - not sure about others. This web site is a great resource.

Thanks, Dick

designbug · Posted: Fri Jul 31, 2009 9:30 am Post subject:

Last night I replaced the main circuit breaker and dc power was restored.

Thanks for everyone's advice, Dick

usmcdory · Posted: Sun May 16, 2010 9:43 pm Post subject:

hey dick, I had a very similar problem today. lost all DC power on my 2009 25 C-dory, GPS, radio, and all rocker switch operated electrical items. Windlass, trim tabs etc continued to work just fine. No lights on my control panel, no power, no nothing. where did you find the main circuit breaker that you replaced. I found a resettable CB near the #1 battery and perko switch which was not popped and I reset anyway. still no power. looked all around the distribution panel in berth behind sterring wheel kick panel but could not find anything that looked
like a main CB for the entire panel. thanks USMC dory

thataway · Posted: Sun May 16, 2010 11:03 pm Post subject:

See the answer to your other post--basically you need to get the volt meter out and check the entire circuit. A volt meter needs to be in every tool kit.

journey on · Posted: Sun May 16, 2010 11:36 pm Post subject:

And I want to add a thought to Bob's very true post. Learn how to use that voltmeter.

For DC circuits that's a simple thing. Even Pat Anderson is learning.

Boris

Wandering Sagebrush · Posted: Mon May 17, 2010 12:21 am Post subject:

journey on · Posted: Mon May 17, 2010 12:10 pm Post subject:

From Pat:

"Now, although there is 13.6 volts at the socket on the circuits for the lights and turn signals (the only ones I checked), when I insert the trailer plug, none of the lights work. The trailer is hooked up, and I have used the trailer frame as ground for my tests, so I don't think it is anything a simple as a ground wire, bu there is a white wire hanging loose out of the trailer harness. "

That was Step 1. For Step 2, he just needs to learn what wires do.

Boris

designbug · Posted: Mon May 17, 2010 1:16 pm Post subject:

It sounds like you found the main circuit breaker. Mine was located near the battery selector switch.

The way I found out that the circuit breaker was bad was by bypassing it. I did this by disconnecting the wires going to the breaker and then briefly touched them together where I noted that power was restored.

I seem to recall that the bad breaker was Sea Dog(?) brand and I replaced it with Blue Seas(?) brand - about $40-$50 at West Marine. I haven't had a problem since.

Thanks, Dick

journey on · Posted: Mon May 17, 2010 8:01 pm Post subject:

Dick, that's one of the beauties of a voltmeter. You don't have to wire around a suspected bad switch, breaker, fuse, etc. What if the breaker had broken because of a fault downstream? You would have connected 30 amps of 110 VAC directly to a short. That would have been more exciting than you'd like to remember.

Voltmeters are good things to use. Saves a lot of guessing and can be quite safe.

Boris